1. Field of Invention
This invention relates to a braking system, and more particularly to an apparatus and method for simplifying pre-trip pneumatic brake system inspections.
2. Description of Related Art
Truck drivers often conduct their own pre-trip inspection of the braking system and, in fact, many truck fleets require the driver to conduct such an inspection as a part of standard operating procedure. For example, the brakes must be applied and the operator conducts a walk around inspection of the vehicle to be sure that all the brakes are properly applied. It is evident when the slack adjustors have moved forward that the brakes are properly applied. In addition, the vehicle operator listens for any audible leaks, checks operation of the stop lights, etc. as a part of the pre-trip inspection.
One manner of conducting the pre-trip inspection is to have a person sit in the cab and depress a foot pedal/treadle while the second person or operator conducts the manual walk-around inspection of the vehicle. This, of course, requires a second person to be present to complete the pre-trip inspection, at least with regard to application of the brakes. Another alternative is to add substantial hardware to the brake system thereby allowing the driver to apply the brakes and then exit the vehicle to conduct an inspection. For example, a complex system using a control valve on the vehicle dash and double check valves in the brake system results in considerable complexity and cost. The additional hardware allows the whole system to interrupt and apply the brakes, although not in a simplified, cost effective manner.
In addition, a need exists for other systems that can apply the signal from an easy control device. For example, a refuse truck could benefit from the use of a work brake where the air actuation system of the foot control valve is operated at a reduced pressure level. A bus door interlock system are other potential uses of an integrated foot control valve actuator.
A need exists for a simplified system and method of reducing the complexity of the pre-trip service inspection in a manner that does not adversely impact on the remaining components of the brake system in a commercially viable manner.
The present invention relates to providing an actuator between a foot pedal or treadle and the foot control valve.
The actuator can be easily actuated with a low capacity control signal.
A preferred form of actuator is a push through plunger that transfers forces from the depression of the foot pedal/treadle to the primary or top piston of the foot control valve and thus allows the foot pedal and control valve to operate in a conventional fashion. In addition, a control port is associated with a push through plunger to independently actuate the foot control valve via a pressure control signal and without using the foot pedal/treadle.
A primary advantage of the invention resides in the simple, low capacity two-way control valve or electrical solenoid to actuate the standard brake control.
Still another advantage resides in the reduced installation time.
Potential leakage points are also minimized with this simplified system.
Overall system complexity is substantially reduced, while permitting the operator to apply the brake system without depressing the foot pedal or treadle.
Still other advantages or benefits of the invention will become apparent to one skilled in the art upon a reading and understanding of the following detailed description.